Electric heater



FIG. 1 is a bottom perspective view of an electric heater in accordance with an embodiment;

FIG. 2 is a bottom view thereof;

FIG. 3 is a first side view thereof;

FIG. 4 is a second side view thereof;

FIG. 5 is a third side view thereof;

FIG. 6 is a fourth side view thereof;

FIG. 7 is a top plan view thereof; and,

FIG. 8 is a top perspective view thereof.

Broken lines represent unclaimed portions of the electric heater and form no part of the claimed design. 

CLAIM The ornamental design for an electric heater, as shown and described. 